Analysis and Design of CMOS Active Dual-Mode Ring-Resonator Filters
Date Issued
2012
Date
2012
Author(s)
Su, Li
Abstract
This dissertation presents analysis and design methods of monolithic K-band ring resonator dual-mode active filter fabricated in standard 0.13 μm complementary metal-oxide-semiconductor (CMOS) technology. The dual-mode ring resonator comprises a quasi-TEM complementary-conductive-strip transmission-line (CCS TL) loop and a shunt metal-insulator-metal (MIM) perturbation capacitor. Two CMOS cross-coupled pairs as active compensation circuits are integrated with the ring resonator symmetrically, forming a robust approach, which both enhances the quality factor of dual modes and reduces the resonator size significantly. Basic characteristics of the filter are discussed, including the unloaded resonant frequencies, transmission zeros, coupling coefficients, Q-enhancement mechanism, linearity, noise and power consumption. Various perturbation schemes and input/output arrangements of the dual-mode resonator topology are also investigated in detail. Variations of resonance frequencies and transmission zeros are analyzed thoroughly under the following situations: the distance between input and output are not 1/4 propagating wavelength, the position of the perturbation capacitor changes, and capacitive or inductive source-load coupling elements exist. Types of ring resonator dual-mode active filters with various perturbation types and input/output arrangement are all implemented and compared, including symmetric type, asymmetric-perturbation-coupled (APC) type, and asymmetric-load-coupled (ALC) type. In implementation stage, for all these types, the areas of the dual-mode active resonators are all 270 by 270 μm2 (0.02 λ0 × 0.02 λ0) without source-load coupling elements, DC biasing circuits and pads, and the sizes of transistors are also the same. For these filters, with similar linearity, noise figure and power consumption characteristics, the great difference of S-parameters are noteworthy for discussion. An identical perturbation element can yield two transmission zeros for a bandpass filter or no transmission zeros depending on the position of the element. Asymmetric coupling prototypes provide two transmission zeros even when no perturbation capacitor added, with the cost of non-reciprocity. With enhanced capacitive source-load couplings, the two transmission zeros become closer, and from this a bandpass filter with 2.58 % fractional bandwidth, 0-dB insertion and skirt factor of 1.87 is implemented. With inductive source-load couplings, a bandstop filter can be implemented. The equivalence between the proposed dual-mode filter topology and the universal building block theory is also discussed, exhibiting a systematic method to design a narrowband, high selectivity, low-profile and low-power bandpass or bandstop active filters in CMOS with high accuracy. Compared with published monolithic dual-mode filters and active filters, the proposed filters are seen possessing small area, narrowband, small insertion loss, high return loss and small skirt factor.
Subjects
Filter design
Active filters
RF circuits
CMOS
Intergrated circuits
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
index.html
Size
23.27 KB
Format
HTML
Checksum
(MD5):305744ecf0d210972b726da15e980d75